The File::Compare::compare function compares the contents of two sources, each of which can be a file or a file handle. It is exported from File::Compare by default.

File::Compare::cmp is a synonym for File::Compare::compare. It is exported from File::Compare only by request.

File::Compare::compare_text does a line by line comparison of the two files. It stops as soon as a difference is detected. compare_text() accepts an optional third argument: This must be a CODE reference to a line comparison function, which returns 0 when both lines are considered equal. For example: